A class was given 5 tests in a term. 20 students got an “A” on at least one test, 13 on at least 2, 12 on at least 3, 7 on at least 4, and 1 student got an “A” on all five tests. How many students got “A”s on exactly 3 tests?

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anonymous · Answer

phaniraj said  subtract at least 3 from at least 4, atleast 3 means they include 3,4,5 medals.atleast 4 means they include 4,5, medals.so of u need only 3 medals than just subtract, can nayone show this to me using a venn diagram please?